[Localization of accessory atrioventricular pathways in patients with manifest premature ventricular excitation syndrome by three-dimensional vector electrocardiography].

Distribution of excitation via ventricular myocardium in patients with accessory atrioventricular pathways (AAVP) was studied using three-dimensional vector ECG. Analysis of the ECGs obtained during the study formed new views on the excitation process in the myocardium in the presence of AAVP, and made it possible to formulate vector ECG (VECG) criteria of AAVP localization. In 30 cases out of 33 it was possible to correctly localize AAVP. Information obtained as a result of VECG analysis made it possible to localize AAVP preoperatively within the limits of 1/14th atrioventricular sulcus with 97.1% accuracy, which is substantially higher than the accuracy of conventional electrocardiographic algorithms. Thus, the study found that in some cases three-dimensional vector ECG allows for substantial increase in the validity of AAVP localization, while in others it is the only sensitive non-invasive method of topical diagnostics of manifest premature ventricular excitation syndrome. Knowledge of the character of intervector interaction during ventricular electric systole makes it possible to predict the character of changes in the trajectory of QRS vector loop in any AAVP localization, i.e. to model the vector loop.